1. Field of the Invention
The present invention relates generally to an apparatus for use in the collection of cell samples from a cytology brush. More particularly, the present invention provides a cell collection apparatus which utilizes a unique combination of fins for agitating the bristles of a cytology brush within a fixative solution, thereby permitting the efficient and complete retrieval of the cell sample from the cytology brush.
2. Background Art
Detection and diagnosis of a variety of diseases, such as cancer, often involves the collection and microscopic examination of a cell sample. Typically, as with the Papanicolaou ("Pap") test, these cell samples are collected from a patient with a type of cytology brush device. After collection, the cell samples must be transferred from the bristles of the brush to some medium that allows for the examination of the cells.
Due to the typically serious nature of the disease that the doctor is attempting to detect, it is critical that the cell samples are completely and accurately transferred from the cytology brush to tile testing medium. Inaccurate retrieval of the cells can result in an inaccurate or delayed diagnosis of any underlying condition. Worse yet, inaccurate or incomplete retrieval of the cell sample could possibly result in the misdiagnosis of a serious medical condition.
Further, as is the case with the Pap smear, many women who have had an inadequate sample taken are reluctant to have the procedure repeated and may be placed at risk for progression of their disease until their next periodic checkup. A delay in the diagnosis of, for instance, cervical or uterine cancer can result in the need for far more radical treatment procedures than would be needed if the cancer were detected earlier. In the worse case, a delay in diagnosis could result in the progression from treatable cancer to a terminal cancer. Thus, a high yield of cells from only one attempt is important.
There are several problems that are encountered when cells are obtained from a cytology brush for later examination using current state of the art procedures. As is typically done after cells have been collected, they are transferred to a microscopic slide for later examination. This is accomplished by wiping the bristles of the cytology brush device directly against the smooth surface of the slide. A fixative is then applied to avoid any deterioration of the cells before the cytology technician and/or pathologist can examine them. However, it is very difficult to transfer all or even a large portion of the cells to a slide by merely wiping the bristles against the smooth slide surface. Thus, valuable diagnostic material is potentially lost. Again, this can increase the risk of an erroneous diagnosis.
This difficulty in transferring the cell sample to a slide is often made worse by the shape or type of cytology brush that is being used. For instance, a spiral shaped cytology brush is commonly used for a variety of cell collection procedures. Due to the shape of the brush, the cells can be transferred to the slide only by wiping, rubbing or rotating the brush against the slide surface. To transfer even a portion of the cells from this type of brush takes excess time and care. Thus, insufficient cell transfer can be very common when this type of brush and cell transfer method is used. Similarly, where a non-spiral type brush device is used, wiping can, at best, remove only a portion of the sample.
In some cases, the presence of mucous or blood or the knowledge that the patient is at high risk, can make the above type of slide preparation inappropriate. In that case, a monocellular preparation may be requested. In this technique, the samples must be transferred from the cytology brush device into a container of a fixative or other similar solution. The container is then centrifuged until all cellular components have: collected at the bottom of the container as a "cell pellet." After the excess fixative is pipetted off, the cell pellet can be spread evenly onto a slide. This provides a slide with very little cellular overlap. Mucous will have gone into solution and any red blood cells will be sufficiently spread so as to avoid obscuring other cells.
However, in this technique, the accuracy of the resulting "cell pellet" is again dependent on the successful and complete transfer of the cell samples disposed on the bristles to the fixative solution within the container. Typically, this transfer is done by placing the bristled end of the cytology brush within the centrifuge tube. The brush is then twirled within the fixative solution contained within the tube, in an attempt to dislodge all of the cells from the bristles. However, the twirling action within the fixative solution alone is often insufficient to dislodge all of the cells that are contained on the brush bristles. This is especially so with a spiral shaped brush, where it is difficult to sufficiently move the bristles within the fixative solution quickly enough so as to dislodge all of the cells. Again, the drawback is that often all of the cell samples are not transferred to the fixative solution, resulting in the same problems discussed above.
In addition, it is often difficult for the technician to hold the collection tube containing the fixative solution, and at the same time, sufficiently move the cytology brush bristles within the solution. To do so, the technician must attempt to hold the collection tube with one hand, and hold the cytology brush with the other, and then twirl, or otherwise move, the brush bristles within the solution so as to dislodge all of the cell samples. This can be awkward, and the potential of spilling and/or contaminating the cell sample and fixative solution is high.